1. Technical Field
The present invention relates to abrasive wheels and, more particularly, to an abrasive wheel with improved composing structure.
2. Description of Related Art
FIG. 3 shows an exploded view of a conventional abrasive wheel which comprises an abrasive component 7, a reinforcement 8, and two covers 9, wherein the abrasive component 7 includes a combining hole 71 in the central region thereof for accommodating the reinforcement 8; the combining hole 71 is provided with a plurality of retaining parts 72 on the peripheral wall thereof; and the two covers 9 contain a plurality of combining tongues 91 for matching plural intervals 73 between each two retaining parts 72 of the combining hole 71 to attach the two covers 9 to the combining hole 71 at both sides thereof respectively; whereby when an abrasive machine drives one of the two covers 9 to rotate, the combining tongues 91 thereof in turn give an impetus to the retaining parts 72 and the abrasive component 7 is therefore pushed to rotate.
However, the structure of said covers 9 is complicated and requires a correspondingly complicated mold that is relatively difficult to be devised to produce the covers 9. Furthermore, it is essential to arrange the reinforcement 8 in the combining hole 71 to reinforce the component 7 for preventing the abrasive component 7 from unduly deforming under the operating force during a user's operation.
Nevertheless, the necessity of the reinforcement 8 can significantly raise the manufacturing costs; also it requires additional difficulty and steps of fabrication. Hence, a need exists for an improvement in the structure of abrasive wheels.
Further, since it is the combining tongues 91 of the covers 9 pushing the retaining parts 72 that rotate the abrasive component 7, stress concentration may detrimentally arise at the contacting areas of the retaining parts 72 and combining tongues 91. After lasting operation, said stress concentration may incur deformation of the retaining parts 72, and as a consequence, the matching relationship between the retaining parts 72 and combining tongues 91 may deteriorate which finally causes breakage of the combining tongues 91.